David Carroll was puzzled.  But he was honest—­“I’m afraid I cannot, Miss Gresham.  I must, at least, try to solve it.”

She paused before him:  figure tensed—­

“Then let me say, Mr. Carroll—­that I hope you fail!”

CHAPTER XVI

THE WOMAN IN THE TAXI

From the Gresham home, David Carroll went straight to headquarters.  Developments had been tumbling over each other so fast that he found himself unable to sort them properly.  He wanted to talk the thing over with someone, to place each new lead in the investigation under the microscope in an attempt to discern its true value in relation to the killing of Roland Warren.

Eric Leverage was the one man to whom he could talk.  And, locked in the Chief’s office, he told all that he knew about the case, detailing conversations, explaining the situation as he understood it, reserving his suspicions and watching keenly for the reaction on the stolid mind of the plodding, practical Chief.

Carroll placed an exceedingly high valuation on Leverage’s opinion—­even though the minds of the two men were as far apart as the poles.  But Leverage was a magnificent man for the office he held:  competent, methodical, intensely orthodox—­but typical of the modern police in contradistinction to the modern detective.

Carroll knew that modern police methods have received a great deal more than their share of unjust criticism.  He knew that the entire theory of national policing is based on an exhaustive system of records and statistics.  It operates by brute force and all-pervading power rather than by any attempt at sublety or keen deduction.  The former is so much safer as a method.  And the combination of the two—­keen analysis, logical deduction and plodding investigation—­can perform wonders, which explains why Carroll and Leverage worked hand-in-hand with implicit confidence in one another.

Leverage listened with rapt attention to the report of his friend.  Occasionally the corners of his large humorous mouth twitched as Carroll touched on one or two of the lighter phases of his investigation—­and once Leverage even twitted him about becoming “one of these here butterfly investigators”—­but Carroll knew that no word of his escaped the retentive brain of the chief of the city’s police force, and that each was being carefully catalogued with truer knowledge of its proper importance than Carroll had yet been able to determine.

“And so,” finished Carroll, “there you are.  The thing is in as pretty a mess as I care to encounter.  Frankly, I don’t know which way to turn next—­which is why I wanted to talk things over.  Perhaps, between us, we can arrive at some solution of the affair—­determine upon some course of action.”

“Yes,” responded Leverage slowly, “perhaps we can.  Only trouble is—­there are so many different ways of spillin’ the beans that we’re takin’ a chance no matter what we do.  Answer me this, David:  if you had to point out one person right now as the guilty one—­which’d you choose?”